(a) Field of the Invention
The present invention relates to instant-cooking dry macaroni and like macaroni-type food products.
(b) Description of the Prior Art
In the past, macaroni products, including spaghetti and vermicelli, have been produced by adding water to starch components consisting mainly of strong wheat flour such as Semolina of the Durum wheat family, uniformly distributing the added water throughout the starch components by kneading the mixture, and thereafter by extracting the kneaded mixture under pressure to shape the material into individual macaroni-shaped pieces or products of any desired shape, and then drying them for a substantially long period of time, often as long as 24 hours. Such macaroni products have and continue to be widely sold in the market.
However, these well known foods are not given an .alpha.-conversion treatment during their manufacturing process. Accordingly, when prepared for consumption these products must be boiled for a substantial length of time, say from 10 to 15 minutes, in order to cook the starch before being served. Thus, these known products are of the instant- or quick-cooking type that can be instantly cooked or transformed into an edible state before serving.
As for those macaroni products which are marked as instantly cookable foods, macaroni products are known which are produced by first subjecting formed raw macaroni pieces to a boiling treatment for .alpha.-conversion of the starch components, and by packing the boiled macaroni pieces in a heat-resistant film or like wrapping sheet, and thereafter subjecting the packed macaroni to a heating-and-pasteurizing step. Also known are macaroni products produced by a manufacturing process similar to that stated above, except that the packed macaroni is subjected to a freezing step at a temperature of about -30.degree. C.
These known instant-cooking macaroni products which have been subjected to a heating-and-pasteurizing step during their manufacturing process can be instantaneously cooked and served only by heating them in hot water or through a similar heating means. However, because these macaroni products having a fairly high content of water, there is the disadvantage that the .alpha.-converted starch components are subjected to .beta.-conversion during storage, and that when the instantly cooked macaroni are served, the person eating them obtains a sense, feel and taste as if the cooked macaroni are not sufficiently boiled and feel like raw wheat flour. This is caused by .beta.-conversion which arises during storage. Thus these known instant-cooking macaroni products are poor in sense, feel and taste when eaten, and in addition thereto, when these known macaroni products are stored for more than a week at room temperature, mold tends to develop on the product, and accordingly they cannot be considered storage stable for an extended period of time.
On the other hand, those products subjected to freezing temperature are superior to those subjected to heating-and-pasteurizing treatment with respect to stability of quality during storage for an extended period of time. However, such frozen products require the additional troublesome step of passing the boiled macaroni through a low-temperature zone. Additionally these frozen macaroni products have the further disadvantage that, as with the heated-and-pasteurized macaroni, the once .alpha.-converted starch components become .beta.-converted during the period in which the macaroni products are defrosted prior to being served, and that thus they give a similar raw wheat flour-like sense, feel and taste when the instantly cooked macaroni are eaten.
Also U.S. Pat. No. 3,537,862 describes a method of obtaining .alpha.-converted pasta by mixing wheat flour and/or other grain powder with water, followed by extruding the mixture directly through a die to form a pasta, and then steaming this pasta at an appropriate temperature while applying hot water thereto, and thereafter drying the product. This known method is suitable for reducing the time required for drying, as viewed from the aspect of manufacture alone, since the pasta is subjected to steaming. Also, this method is able to eliminate the development of muddiness of the surfaces of the product which, otherwise, would be caused by the exudation of those starch components which takes place when the pasta is boiled prior to being served to a consumer. However, the product obtained according to this known method requires that the product be boiled to elevate the .alpha.-conversion to the requisite edible level in order to serve to the consumer, and thus this product cannot be rendered to an edible state during a very short period of time by immersion in hot water. If, however, it is intended to elevate the .alpha.-conversion degree of the pasta to solve such inconvenience as stated above, adjacent portions of products tend to stick to each other and also the shape of the pasta tends to deform during the steaming thereof, resulting in uneven .alpha.-conversion. As a result, such a product will not transform uniformly to the edible state when immersed in hot water, and accordingly will fail to give the consumer a good sense, feel and taste. As such, this known method does not attain the object of the present invention. Additionally large numbers of pasta pieces stuck together is generally unacceptable to the consumer.
Furthermore, there is known a manufacturing method of obtaining .alpha.-converted pasta by mixing, without heating, wheat flour and water, and extruding the resulting mixture dough under a high temperature and high pressure, and thereafter drying same, as stated in U.S. Pat. No. 4,044,165. However, this method requires high temperature extrusion of the flour-water mixture in order to enhance the degree of .alpha.-conversion of the product. Also the water contained in the material boils during the extrusion process, causing extensive expansion of the material, leading to an uneven configuration of the final product, resulting in a marked lowering of the commodity value of the product. Furthermore, under such heating condition, no sufficient .alpha.-conversion degree of the product can be attained, and therefore the product will not be rendered to an edible state by its mere immersion in hot water. If, therefore, the amount of the water added is decreased at the time of mixing to prevent the occurrence of this expansion, this results in a shortage of water in the mixture which is necessary for effecting the required degree of .alpha.-conversion, leading to the result that the degree of .alpha.-conversion of the extruded product becomes low. This, in turn, will give to the consumer a feeling like raw wheat flour even when the product is transformed to edible state by immersion in hot water. Thus, the product so obtained has the disadvantage represented by a loss of good sense, feel and taste. As such, this procedure is unable to attain the objects of the present invention.
These known products, sometimes labeled as instant-cooking macaroni products, generally further have the disadvantage that when hot water is poured onto the macaroni products, they tend to cause the hot water to become turbid and cloudy in the cooking water due to partical exuding or dissolving of starch components in the hot water, resulting in a loss of good shape of the individual pieces of macaroni as well as a loss of sense, feel and taste. In some cases the macaroni pieces immersed in hot water tend to stick to each other locally.
As stated, the known instant-cooking macaroni products have various disadvantages and inconveniences. The present invention provides a macaroni-type product free from such difficulties.
The present inventors, therefore, have conducted research and many experiments to resolve the foregoing problems encountered in the prior art, and as a result they have arrived at the present invention based on their discovery that, by first forming a granular mixture of grain flour consisting mainly of wheat flour, especially of Semolina flour of the Durum wheat family, while avoiding to the extent possible causing the mixture to become kneaded during the mixing step, a fully acceptable product is obtained. At the same time the water content of the mixture is adjusted so as to be in the range of 25 to 40% by weight, relative to the weight of the starch-containing components of the mixture, and the mixing is continued until the granules of the mixed material are distributed evenly throughout the body of the mixture. Thereafter the mixture is subjected to a preliminary steaming to bring about an .alpha.-conversion degree of the starch-containing components of the mixture of from 60% to 80%. In addition the reticulate structure of the protein, i.e. gluten, contained in the mixture becomes fixed as this gluten progressively undergoes denaturalization due to the application of heat during the steaming step resulting in those parts of the starch-containing components which have become glue-like becoming enclosed in the reticulate structure. This inhibits the granules from exuding to adhere to the surface of the mixture, which means that the surfaces of the subsequently molded macaroni products do not become sticky.
The present inventors have also found that this reticulate structure of gluten contributes to the formation of a product having an appropriate degree of viscosity and resiliency of the molded macaroni pieces and a desirable texture thereof. When the material is appropriately shaped into individual molded pieces by means of, for example, an extruder, there occurs no development of phenomenon such as the surfaces of the individual molded pieces of macaroni locally sticking to each other or that the configuration of the molded pieces will become deformed. These problems have been encountered in conventional foods which have been caused by excessive .alpha.-conversion during the boiling step in the manufacturing process.
The present inventors have further found that, through their process, there can be obtained molded products of individual macaroni pieces which are uniform in configuration relative to each other, which do not develop muddiness on the surfaces of the individual molded pieces and which are free of stickiness between contacting portions of these molded pieces.
The present inventors have also found that, even when the surfaces of the molded pieces which have been preliminarily steamed for an .alpha.-conversion degree of from 60 to 80% are contacted with water and when these water-carrying pieces of the material are subjected to further steaming until an .alpha.-conversion of the starch-containing components of at least 85% is reached, in order to enhance the ability to these molded pieces to be instantaneously rendered to an edible cooked state, no exudation of the remaining starch-containing components occurs. This exudate is of a glue-like nature, and thus avoiding the exudate during this further steaming no sticking between portions of the individual molded pieces occurs nor are the pieces deformed. Further a uniform .alpha.-conversion is established throughout the pieces. This means that the material does not stick onto the surfaces of the molding apparatus, and that uniform molded pieces can be obtained.
By drying the resulting molded pieces of material, the dried pieces are found to possess a fine porous structure having a pore diameter of 5.0-20.0 microns, which structure enables them to be transformed very quickly to an edible cooked state by immersion in hot water of about 85.degree. C. or higher for a period of 5 minutes or less. Thus, there are obtained instant-cooking dry macaroni and like macaroni-type products which exhibit good sense, feel and taste when eaten, and which are storage stable when stored for an extended period of time, for instance for a period over one year.